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16311 Spring 2020 – Introduction to Robotics Guest Lecture/ p1 © 2020 Dimi Apostolopoulos

Engineering Robotic Systems: Process,

Critical Considerations, and a Case Study

Dimi Apostolopoulos

Guest Lecture to 16311 Introduction to Robotics

February 5, 2020


This lecture

Methods to develop robotic systems

Attributes of robotic systems

An illustrative case study with important observations


Introduction

Dimitrios (Dimi) Apostolopoulos

Senior Systems Scientist

The Robotics Institute

Carnegie Mellon University


Creating advanced robotics systems from within CMU

Groups/Centers

Departments

Schools

UniversityCarnegie Mellon

University

6 other schools

School of Computer Science

Many other departments

Robotics Institute

Other Centers

NREC

• Created in 1979

• Over 900 people

• > 400 grad students

• > $60M in R&D per year

• Created in 1995

• Over 130 employees

• Received >$370M in R&D

funding

• 50% from commercial

• > $30M in R&D per year


NREC is in the middle of one of most dynamic clusters of

robotics companies in the world

Lawrenceville, Pittsburgh


Inventing, engineering, and field-validating prototypical, yet

ruggedized robotics in real-world applications

Robotics for autonomous mapping and

remote inspection of platinum mines

(South Africa)


Robotics to change the state of practice and add value

Robot for inspection of cooper ore

slurry pipelines (Chile)


All robotic systems require multidisciplinary teams to create

them, and involve complex constructs of hardware and software

Motion Planning & Execution

Positioning

Mapping

3D Range Sensing

Electro-Mechanical Design

Image/sensor Processing

Unmanned Vehicle Design

Autonomy

System Integration & Testing

Operator Interfaces

Manipulation

Machine Learning

It is imperative to apply systematic processes in the

development of robotic systems


We use Systems Engineering to manage requirement-driven

engineering of robotic systems

Reference B. McDonough, 2013


Generally there are three phases in the development of a system

Concept

Development

Engineering

Development

Post

Development

Operational

Need

Technological

Opportunities

Defined System

Concept(s)

Detailed

Requirements

Detailed

Specifications

Validated

System

Fielded

System

Detailed

Documentation

Inspired by A. Kossiakoff, W. N. Sweet, S. J. Seymour, S. M. Biemer, 2011


We use the V method that goes top-down to design, and

bottom-up to test and validate compliance to requirements

Requirements

Development

System

Architecting

Component

Design

Fabrication and

Assembly

Subsystem

Design

Unit

Testing

Subsystem

Testing

Integrated

System Testing

Acceptance

Testing


For larger, more complex systems and projects we apply the V

method


We also use Agile methods, which allow for incremental

development

1 2 N

START

FINISH

http://tryqa.com/what-is-agile-model-advantages-disadvantages-and-when-to-use-it/

…

http://tryqa.com/what-is-agile-model-advantages-disadvantages-and-when-to-use-it/


For retrofits-for-automation and subsystem R&D we apply agile

methods

Sensing, autonomy, and

tooling retrofits


Attributes of robotic systems


Systems entail

• Hierarchy of subsystems and components

• Capabilities and characteristics (functional, non-functional)

• Relationships between subsystems and components

• State of an component at a point in time

• Behaviors: Sequences of component states over time

• Processes: Sequence and timing of behaviors


Systems have hierarchy, attributes, relationships,

states, behaviors, and processes


System hierarchy

System

Subsystem Subsystem

Component Component Component

Subsystem


Multiple possible ways to partition a robot into

subsystems. Contrast monolithic vs. modular

Collision Avoidance

Sensors

Environment

Perception Sensors

Ride Smoothing

Assembly

Drive Assembly Heat Management

Subsystem


Systems have capabilities and characteristics

Functional Non-Functional


System capabilities and characteristics

FunctionalDrives

Steers

Controls

Senses

Perceives

Plans

Detects

Avoids

Communicates

Maps

Localizes

Analyzes

Interprets

Summarizes

Diagnoses

etc.

Non-FunctionalWeight

Color

Dimensions

Cost

IP rating

Aesthetics

Ergonomics

Noise level

Power capacity

Computing capacity

Reliability

Durability

Maintainability

Serviceability

Compliance

etc.


Relationships in systems

• How the subsystems/components combine to contribute to

the system’s purpose

• In an optimized system, the subsystems are connected in a

way that their relationships yields] maximum effectiveness

Capturing the relationships between subsystems and

components is essential to create system architectures,

which we then use in design and engineering


Let’s examine relationships within a system

Robotic

Mine Profiler

Autonomously

Navigates

Autonomously

Maps

Avoids

Collisions


How to identify relationships within a system

Pose Estimation Localization

Mapping

AutonomySensing

Collision

Avoidance


How relationships affect what the system will be


Mapping

Autonomy

Collision

Avoidance

Sensing


How relationships affect what the system will be


Sensing

Mapping

Autonomy

SensingCollision

AvoidanceSensing

Sensing


Properly defining a systems relationships impacts the form

and function of a system

Distributed Low-cost LiDAR & Cameras Dedicated Medium Cost LiDAR and Cameras

High-end LiDAR Scanner


Systems also have

State

– Situation of a component (or set of components) at a point in

time

– Static, dynamic, in-between

Behavior

– Connected series of changes in state over time

Process

– Set of all behaviors with their relative sequence and timing


State, Behavior, and Process

Sensing Pose Estimation Localization Autonomy

Remote Control

SensingCollision

AvoidanceSensing

Mapping

On Off

Sensing


State, Behavior, and Process

Localization

Sensing

Autonomy

Remote Control

SensingCollision

AvoidanceSensing

Mapping

On Off

Pose EstimationSensing


Takeaway points

The development of robotic systems requires the application

systems engineering methods. Applying such methods is

essential to ensure traceability of requirements and

rationalization of design and engineering decisions made

along the way.

All systems including robotic systems have important

attributes: Hierarchy, capabilities and characteristics,

relationships, states, behaviors, and process. Carefully

designing and engineering these attributes result in a

successful system.